Hey, Mark or Charles,
There's now another post about font menu's being greyed out and inoperative, (one from Todd also).
I haven't found a reference to them in the archive, can you let us know the status of these problems?

In Mac OS X, bold and italics only works if the font you are using supports bold and italics. What this means is that if you create document in Word on a PC or in a Carbon application on the Mac, you may be able to use a font and bold and italicize it. But, when you try to open it in a Cocoa application like Nisus Writer, the bold and italics will not appear. (Though it is saved in the file.)

The good news is that we have fixed this issue for the next release of Nisus Writer. You will be able to bold or italicize any font. If the font does not support it, then we will fake it. (This will work only under OS X 10.3).